如何在 MySQL 中实现 INTERSECT

如何解决如何在 MySQL 中实现 INTERSECT

这是我当前的查询。我今天发现了 INTERSECT，但是 MysqL 不支持它。谁能给我一些关于如何改进这个查询的建议？它给了我我正在寻找的结果，但速度很慢。

如果有帮助，我正在与运动队合作，并过滤统计数据。我过滤主队，然后是客队。我使用了 count(id) 方法，因为我只想返回在 both 查询中找到的夹具 ID，所以我认为 INTERSECT 会很完美。

    select id,count(id) as count from (
    
    select f.id,f.etc,etc
    from fixtures f
    inner join team_stats t on f.id = t.fixture_id and f.league_id = t.league_id and f.home_id = t.team_id
    where f.status in ('FT','AET','PEN','FT_PEN') and
    unix < 1619927451 and
    played_overall between '11' and '60' and
    scored_1h_home_avg between '0.7' and '6' and 
    o05_1h_goals_overall_per between '76' and '100' and 
    first_goal_total_avg between '0' and '35' and 
    scored_o05_1h_home_per >= 69
    
    UNION ALL
    
    select f.id,etc
    from fixtures f
    inner join team_stats t on f.id = t.fixture_id and f.league_id = t.league_id and f.away_id = t.team_id
    where f.status in ('FT','FT_PEN') and
    unix < 1619927451 and
    played_overall between '11' and '60' and
    conceded_1h_away_avg between '0.7' and '6' and 
    first_goal_total_avg between '0' and '35' and 
    o05_1h_goals_away_per between '77' and '100'
)    
    x group by id HAVING count(id) > 1

解决方法

您可以使用 exists 来获得您想要的：

select f.id
from fixtures f
inner join team_stats t on f.id = t.fixture_id and f.league_id = t.league_id and f.home_id = t.team_id
where f.status in ('FT','AET','PEN','FT_PEN') and
unix < 1619927451 and
played_overall between '11' and '60' and scored_1h_home_avg between '0.7' and '6' and o05_1h_goals_overall_per between '76' and '100' and first_goal_total_avg between '0' and '35' and scored_o05_1h_home_per >= 69

and exists(

select 1
from fixtures f2
inner join team_stats t on f2.id = t.fixture_id and f2.league_id = t.league_id and f2.away_id = t.team_id
where f2.status in ('FT','FT_PEN') and
unix < 1619927451 and
played_overall between '11' and '60' and
conceded_1h_away_avg between '0.7' and '6' and first_goal_total_avg between '0' and '35' and o05_1h_goals_away_per between '77' and '100'
and f1.id=f2.id)

另一种变体可以在没有 union all 的情况下组合两个查询。如果您的查询产生正确答案，那么这也应该这样做。

select id,count(id) as i_count 
from fixtures f
inner join team_stats t on f.id = t.fixture_id and f.league_id = t.league_id 
where f.status in ('FT','FT_PEN') and
unix < 1619927451 and
played_overall between '11' and '60'    

and ((f.home_id = t.team_id and and scored_1h_home_avg between '0.7' and '6'  o05_1h_goals_overall_per between '76' and '100' and first_goal_total_avg between '0' and '35' and scored_o05_1h_home_per >= 69)
or (f.away_id = t.team_id and conceded_1h_away_avg between '0.7' and '6' and first_goal_total_avg between '0' and '35' and o05_1h_goals_away_per between '77' and '100'))

group by id HAVING count(id) > 1

如果我的操作正确，两个查询中的情况相同：

select f.id,f.etc,etc
from fixtures f join
     team_stats t
     on f.id = t.fixture_id and f.league_id = t.league_id and f.away_id = t.team_id
where f.status in ('FT','FT_PEN') and
      unix < 1619927451 and
      played_overall between '11' and '60' and
      conceded_1h_away_avg between '0.7' and '6' and 
      first_goal_total_avg between '0' and '35'

那么你需要这两个条件：

scored_o05_1h_home_per >= 69
o05_1h_goals_away_per between '77' and '100'

如果是这样，聚合可能是最简单的解决方案：

select f.id,'FT_PEN') and
      unix < 1619927451 and
      played_overall between '11' and '60' and
      conceded_1h_away_avg between '0.7' and '6' and 
      first_goal_total_avg between '0' and '35'
group by f.id
having sum(scored_o05_1h_home_per >= 69) > 0 and
       sum(o05_1h_goals_away_per between '77' and '100')

我还注意到您在看起来像数字的内容周围使用单引号。如果这些真的是数字，那么去掉单引号。不要混合类型。如果值以字符串形式存储，则比较以字符串形式而不是数字形式存储，并且可能不会按照您的预期进行。